The Chinese authorities have begun a three-month drive to seize videos, compact discs, tapes and magazines they deem pornographic or reactionary.

"Publications with serious political problems have appeared in a number of places," said Yu Youxian, the head of China's press and publications administration.

He said incentives would be offered for information about illegal publications and two telephone hotlines would be set up.

Launching the measures Mr Yu hailed the successful closure of more than 50 illegal video compact disc production lines.

But he admitted that in parts of the country, the smuggling of what he called pornographic videos and other electronic products remained rampant.

In one recent case, customs in Guangdong, across the border from Hong Kong, are reported to have seized almost 1.5m such items.

Mr Yu said the "winter offensives" organised since 1990 have brought "noticeable achievements."

The last offensive brought the seizure of 12.61 million printed publications, 6.48 million audio and video cassettes and 1.86 pirated video compact discs, he said.

More than 1,000 printers were shut down as well as eight publishing houses.

The Chinese Communist Party has called for severe punishments of the authors of clandestine publications.

"Forceful measures must be introduced to ensure a stable, prosperous publication market and to contribute to a peaceful and united society," said a senior party official, Liu Zhongde.

The official People's Daily newspaper said the lack of good, cheap domestic products made it easier for pirate manufacturers.